Question about tranny rebuild. Won't shift to 3rd.

[PSIcho]

Searched around but couldn't find an exact match for my cars symptoms. Anyway, I just put in a used tranny that was rebuilt about 10K or so miles. The problem is that it won't shift to 3rd gear at all, with the car running or not. In fact, I even tried removing the shift linkage on the tranny and moving it manually so that I can eliminate the shifter and shift linkage out of the equation. It'll go to every other gear with no problem. No signs of grinding or noise on the other gears as well so I'm assuming there's no other problem but perhaps a shift fork or rail. Does any body have any idea?

Also, if it is a shift fork or rail, would that be something I can replace easily? Looking at the VFAQ for the tranny rebuild requires a press and lotsa clearance checks. I've done all work in my car so I'm pretty competent. However, I don't really want to perform a total rebuild myself or drop $1000 on sending it out for a rebuild if its something minor for now.

Please help. Thanks.

 

[JackM]

It could be that the synchro slider and the gear dog engagement teeth are so worn out and damaged that it won't go into 3rd. I don't think it could be the fork or rail as that would affect 4th gear too.

Could also be something damaged in the shift shaft assembly too. Either way, the unit sounds like it will have to be torn down in order to figure out what happened.

Jack

 

[PSIcho]

It could be that the synchro slider and the gear dog engagement teeth are so worn out and damaged that it won't go into 3rd. I don't think it could be the fork or rail as that would affect 4th gear too.

Could also be something damaged in the shift shaft assembly too. Either way, the unit sounds like it will have to be torn down in order to figure out what happened.

Jack

I was hoping that you'd be the one to answer my question, I'm glad Anyway, I forgot to mention that when I first installed the tranny that it did go into 3rd for a couple of times when I was test driving it around the neighborhood but disappeared on the way back. When it did go in there were no grinding noise or any other noise at all when it was working. Does this change anything? BTW, it does have Quaife in it as well not sure if it makes a difference.

Lastly, my plan is to open the tranny up and try to do it myself but if I get to the point where I can't go any further as far as fixing it, then I'll send it out. Do any of what you believe might be wrong can be a one or two part replacement or is it more extensive. I appreaciate the feedback. I really like working on my car but just to a point.

 

[PSIcho]

Anybody else has done a tranny rebuilt that can shed some light on how difficult it'll be to replace those parts that JackM mentioned? I don't have access to a press so I don't think I'd want to do a rebuild myself but if what JackM mentioned was something simple to replace then I think I'll try it first before sending the entire tranny out. Thanks.

 

[twicks69]

It is not too hard to dissassemble a transmission and put it back together. The real difficulty comes into KNOWING what to look for after you have taken it apart.

With the 3rd gear shifting difficulty you are dealing with, Jack is right; it could be a worn out 3rd gear (gear is pressed onto the input shaft), or the 3rd gear of the intermediate shaft (the intermediate shaft is cast with 3rd/4th gears on it), a damaged synchro on 3rd (or a shattered synchro), shift rail damage or debris in the way between the 3/4 hub/slider and the gear engagement teeth, etc.

Having a professional take a look at it; and KNOW what to look for will make a world of difference, and is WORTH the shipping cost.

Also, bandage fixing the tranny with just a new 3rd gear or 3rd synchro may not fix the problem fully. It could also be an issue with improper preloads or worn out tapered roller bearings on the intermediate shaft, causing additional thrust loads on both gear sets, and pushing the 3rd/4th gears away from each other under load, further increasing the potential for additional damage, or other issues like a damaged shift rail end.


All in all, I needed to learn to do these myself because I couldn't afford to have others do them for me. I am currently on my 13th race transmission. 10 were shep/tre trannies/beyond redline trannies, then the last 3 were my rebuilds.

Racing takes a hell of a toll on parts when you are looking for 1.4 60's. I can certainly say that the Quartermaster clutch has dropped breakage substantially because of preloading off the line; reducing the shockload the transmission sees.


If you want to take it apart, please give Jack or Shep or Jon at TRE a call first and describe the issues you are dealing with before you touch it. More than likely, they will all tell you to bring it to them and get it checked/rebuilt. And I agree with them.

After contacting them, and feeling like you still want to do it yourself, then read this:
2G transmission rebuild FAQ -- from www.vfaq.com

This is an excellent rebuild how-to that shows you mostly what you need to do. You will still want to get your hands on the Mitsubishi technical manual that overviews pressing off/on the gears and preloads, etc. (I can't find it off hand right now).

It does use several specialty tools, gear splitters, a press, and airtools, along with alot of other tools in standby.

If you want it back fast, send it to a pro. If you want to have a transmission apart for a duration of time, then do it yourself, find your replacement parts through CAPS, order them from a dealer, and rebuild it.

 

[PSIcho]

Thanks much Twicks, I think I got what I needed from your reply. I now have two broken trannies, I was planning on taking the other tranny apart for learning experience but it seems that from what you describe that it's a little more involved that what I want to do. Perhaps its time for that rebuild, but hey I got a nice deal on a Quaife off this broken tranny deal as I only paid $200

Now the question is which taller 5th gear should i get? 8% or 16%

Again, thanks for the reply guys!!!

 

[PSIcho]

RESOLVED UPDATE!! Just as an FYI, the problem turned out to be a broken bolt inside the tranny that was preventing it from shifting. Fortunately, it didn't kill any of the gears. After taking that out and replacing some bearings, its all butter.

 

[twicks69]

RESOLVED UPDATE!! Just as an FYI, the problem turned out to be a broken bolt inside the tranny that was preventing it from shifting. Fortunately, it didn't kill any of the gears. After taking that out and replacing some bearings, its all butter.

Excellent! That is great to hear that it was only very minor!